滑动相关器被广泛应用于信道特性的测量，但航空遥测信道的大延迟衰落会严重限制测量系统的测量性能，甚至测量无法完成。为了更加精确地测量航空遥测信道，本文提出一种基于Zadoff-Chu（ZC）序列的滑动相关器，研究其在航空遥测信道测量系统中的信道测量能力。与传统分析方法不同，首先从频域给出测量系统中每个干扰分量的解析表达，然后给出多径环境下的平均动态范围，最后分别基于ZC序列根、归一化滑动因子、信噪比（SNR）和测量序列长度等干扰因素的仿真分析每个干扰分量对测量性能的影响。仿真结果表明：所提的滑动相关器会明显抑制由加性噪声产生的干扰，且在归一化滑动因子大于2和信噪比大于10 dB时，测量性能比传统滑动相关器至少提高2 dB，因此所提滑动相关器的滑动相关峰会更加明显，能更利于航空遥测信道中每条多径分量的检测。
Sliding correlators are widely used in the measurement of channel characteristics, but large delay fading in the aeronautical telemetry channel severely limits the performance of the measurement system, and even cause the system to be unable to complete the measurement. To measure aeronautical telemetry channels more accurately, this paper proposes a sliding correlator based on Zadoff-Chu(ZC) sequences. The channel sounding ability of the correlator in the measurement system of aeronautical telemetry channels is studied. Different from traditional analysis methods, the analytical expression of each interference component in the measurement system is first given from the frequency domain. Second, the average dynamic range in the multipath environment is given. Finally, the influence of each interference component on the measurement performance is analyzed based on the simulation of the ZC sequence root, normalized sliding factor, Signal-to-Noise Ratio(SNR) and measurement sequence length. Simulation results show that the proposed sliding correlator can suppress obviously the interference caused by additive noise. Moreover, when the normalized sliding factor is greater than 2 and the SNR is greater than 10 dB, the measurement performance of the correlator proposed is at least 2 dB higher than that of the traditional sliding correlator. Therefore, the sliding correlation peak of the sliding correlator proposed is more obvious, so the correlator is more conducive to detection of each multipath component in the aeronautical telemetry channel.
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